In this review, we will be comparing MSX Sub 300 and KC62, two Powered Subwoofer speakers from Cambridge Audio and KEF. Being Powered subwoofers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them. Let's have a brief look at the main features of Cambridge Audio MSX Sub 300 and KEF KC62 first before getting into our more detailed comparison.
The sections below take each area in turn: driver and amplifier, frequency response, physical size and connectivity.
Drivers
The efficiency of a subwoofer is directly proportional to the total radiating are squared hence the woofer quantity and diameter.Cambridge Audio MSX Sub 300 and KEF KC62 have a totally different setup: the Cambridge Audio MSX Sub 300 features 1 x 8-inch drivers whereas the KC62 features 2 x 6.5-inch drivers.
Frequency Response
MSX Sub 300 has a frequency range of 31-200 Hz whereas KC62 has a frequency range of 11-200 Hz. With a minimum frequency of 11Hz, the KC62 can go significantly deeper on the low side and provide stronger bass compared to the MSX Sub 300's min frequency of 31Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Subwoofer class in our database.
Low Frequency
Subwoofer Speakers
Cambridge Audio MSX Sub 300
High Frequency
Subwoofer Speakers
Cambridge Audio MSX Sub 300
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Cambridge Audio MSX Sub 300's and KEF KC62's external dimensions. Cambridge Audio MSX Sub 300 has external dimensions of 312.7 x 266.7 x 311.2mm () whereas KEF KC62 has external dimensions of 245.0 x 258.0 x 281.0mm (9-5/8inch x 10-1/8inch x 11-1/16inch).
Cambridge Audio MSX Sub 300 is clearly the larger of the two speakers. Its body is 8.7mm wider, 67.7mm taller and 30.2mm deeper than KEF KC62.
Size, drawn to scale
Both speakers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same surface and pushed back to the same wall, so the deeper one visibly sticks out further.
Cambridge Audio MSX Sub 300 needs about 14% more floor or shelf area. Cambridge Audio MSX Sub 300 is 30mm deeper, so it stands that much further out from the wall. Cambridge Audio MSX Sub 300 is 68mm taller.
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the Cambridge Audio MSX Sub 300 is approximately 830.0cm2 / 128.7inch2 and base area of the KEF KC62 is approximately 725.0cm2 / 112.4inch2. The MSX Sub 300 requires 14% more surface area than the KC62 which gives it a small disadvantage on placement in tight spaces.
Weight Comparison The weight of a subwoofer may become an important factor if you need to move and reposition the unit often to find the optimal positioning, also known as 'Subwoofer Crawling'. The Cambridge Audio MSX Sub 300 weighs 7.48kg / 16.5lbs and the KEF KC62 weighs 14.05kg / 30.9lbs. This makes the KC62 88% heavier than the MSX Sub 300.
Here is a comparison of how MSX Sub 300 and KC62's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
Cambridge Audio MSX Sub 300
 Woofer Size |
8 inches
vs
6.5 inches
|
Larger woofer |
 Price per pair* |
549USD
vs
1500USD
|
costs less (*prices may change depending on the seller, location and time) |
| Number of Woofers |
2
vs
1
|
More woofers |
| Low Frequency Response |
11 Hz
vs
31 Hz
|
Generates deeper bass |
 Height |
245mm
vs
312mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
725cm2
vs
830cm2
|
Takes less floor space |
Size, drawn to scale
Both subwoofers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same floor and pushed back to the same wall, so the bigger one visibly takes more of the room.
Cambridge Audio MSX Sub 300 needs about 14% more floor area. Cambridge Audio MSX Sub 300 stands 30mm further into the room. Cambridge Audio MSX Sub 300 is 68mm taller.
| General |
Cambridge Audio MSX Sub 300 |
KEF KC62 |
| Brand |
Cambridge Audio |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Frequency Response |
31-200 Hz |
11-200 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
1000-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
2 |
| Woofer Size |
8" |
6.5" |
| Woofer Composition |
|
|
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
side |
Physical Specs |
|
|
| Height |
312.7mm (12.3") |
245.0mm (9.6") |
| Width |
266.7mm (10.5") |
258.0mm (10.2") |
| Depth |
311.2mm (12.3") |
281.0mm (11.1") |
| Weight |
7.48kg (16.5lbs) |
14.05kg (30.9lbs) |
| Enclosure |
|
Acoustic Suspension |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
2 Years |
| Labor Warranty |
2 Years |
2 Years |
A passive radiator subwoofer against a sealed one. That is the most consequential line on this page: it decides how the bass rolls off, how it behaves in a small room, and how much output you get for the size of the box.
| Area | Better | Why |
|---|
| Bass depth | B | KEF KC62 goes deeper - 11Hz against 31Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | B | KEF KC62 has the bigger amplifier - 1000W against 300W RMS, about 5.2dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | KEF KC62 moves more air: 2 x 6.5" against 8" is 1.32x the cone area, not the 1.15x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | Cambridge Audio MSX Sub 300 is passive radiator - a passive radiator behaves like a port without the pipe noise, and suits a slim cabinet; KEF KC62 is sealed - a sealed box rolls off gently and is usually the easier one to integrate in a small or awkward room. Neither is better in the abstract; ported tends to suit films and sealed tends to suit music, and both generalisations have exceptions. |
| Cabinet size | depends | KEF KC62 is about 32% smaller by volume. In a subwoofer that is a real trade rather than a preference: box volume is how you get output low down without a bigger amplifier. |
| Price | A | Cambridge Audio MSX Sub 300 costs less - $549 against $1,500, about 63% less. |
A Cambridge Audio MSX Sub 300 B KEF KC62
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both subwoofers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
The usual trade-off: KEF KC62 measures better, Cambridge Audio MSX Sub 300 costs about 63% less. In a normal room, placement will make a bigger difference than the gap between these two. Films or music? If this is mainly a home cinema, Cambridge Audio MSX Sub 300 will hit harder for the money; if it is mainly for music in a normal-sized room, KEF KC62 is usually the easier one to make sound right. Two small subwoofers beat one big one in most rooms - a pair evens out the room modes in a way no single box can, whatever its specs. At $549 each, two Cambridge Audio MSX Sub 300 cost about $1,098 against $1,500 for one of the other, which is worth a thought.
One thing outweighs everything above: where the subwoofer stands. Room modes can add or remove 10dB or more at a given seat, which is far larger than any difference on this page. Before spending more, try the sub in two or three positions - the crawl test, where you put it in the listening seat and crawl the room to find where the bass sounds best, costs nothing and usually beats an upgrade.